Techniques are known for exercising and rehabilitating mammalian joints, particularly long bone joints of humans that actively participate in athletic events. For the case of human knee joint injuries, it is known to perform articulation motion exercises repetitively to a user's joint to condition the joint during rehabilitation. However, there exists a need to further improve the manner in which such exercises extend and hold a joint past a normal range of motion when the joint has restricted motion resulting from injury or degeneration.